Here's away to get really thick tomato sauce in a short time.
Simply simmer your pureed tomatoes slowly in a heavy pot but don't stir. You'll notice that the warer evaporates from the tomatoes and rises to the top. Skim this water off the top, run it through a strainer, and return any solid matter back into the pot. Using this method, it won't be long at all before you get a pot of thick sauce.
Note: you can save the light pink water you strained for soup stock or tomato juice.